Vulnerability in Golang Protobuf

CVE-2021-3121

An issue was discovered in GoGo Protobuf before 1.3.2. plugin/unmarshal/unmarshal.go lacks certain index validation, aka the "skippy peanut butter" issue.

EPSS: 0.035 (87.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-3121?
CVE-2021-3121 is a high-severity vulnerability in Golang Protobuf, classified under Improper Validation of Array Index. CVSS score: 8.6/10. Published 2021-01-11.
How severe is CVE-2021-3121?
High severity. CVSS v3 base score is 8.6 out of 10.
Is CVE-2021-3121 known to be exploited?
11 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.